一类方程系统的中心焦点判定问题

On Detrmining the Central Focus of a Type of Equation Systems

就y·=-∑4i=1αixi-(∑2i=0αixi)y,x·=y类方程的中心焦点判定,给出了2个判定定理.通过直接计算,可简化对此类系统的中心焦点的判定.

This paper seeks the method to determine the central focus of a type of equation systems such as y·=-∑4i=1α_ix^i-(∑2i=0α_ix^i)y,x·=y, by two theorems. Thus the determination of the central focus of these systems can be simplized through direct calculation.